[PATCH 1/9] PCI: endpoint: Introduce pci_epc_bar_type BAR_64BIT_UPPER

Manikanta Maddireddy mmaddireddy at nvidia.com
Mon Feb 23 14:57:35 AEDT 2026


On 18/02/26 3:27 am, Frank Li wrote:
> On Tue, Feb 17, 2026 at 10:27:07PM +0100, Niklas Cassel wrote:
>> Add a pci_epc_bar_type BAR_64BIT_UPPER to more clearly differentiate
>> BAR_64BIT_UPPER from BAR_RESERVED.
>>
>> This BAR type will only be used for a BAR following a "only_64bit" BAR.
>>
>> This makes the BAR description more clear, and the reader does no longer
>> need to check the BAR type for the preceding BAR to know how to interpret
>> the BAR type.
>>
>> No functional changes.
>>
>> Signed-off-by: Niklas Cassel<cassel at kernel.org>
>> ---
> Reviewed-by: Frank Li<Frank.Li at nxp.com>
Tested by: Manikanta Maddireddy <mmaddireddy at nvidia.com>
>
>>   drivers/pci/controller/dwc/pci-layerscape-ep.c |  4 ++--
>>   drivers/pci/controller/dwc/pcie-keembay.c      |  6 +++---
>>   drivers/pci/controller/dwc/pcie-qcom-ep.c      |  4 ++--
>>   drivers/pci/controller/dwc/pcie-tegra194.c     |  2 +-
>>   drivers/pci/controller/dwc/pcie-uniphier-ep.c  | 10 +++++-----
>>   drivers/pci/controller/pcie-rcar-ep.c          |  6 +++---
>>   drivers/pci/endpoint/pci-epc-core.c            |  3 ++-
>>   include/linux/pci-epc.h                        |  5 ++++-
>>   8 files changed, 22 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
>> index a4a800699f89..5a03a8f895f9 100644
>> --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
>> +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
>> @@ -251,9 +251,9 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev)
>>   	pci->ops = pcie->drvdata->dw_pcie_ops;
>>
>>   	ls_epc->bar[BAR_2].only_64bit = true;
>> -	ls_epc->bar[BAR_3].type = BAR_RESERVED;
>> +	ls_epc->bar[BAR_3].type = BAR_64BIT_UPPER;
>>   	ls_epc->bar[BAR_4].only_64bit = true;
>> -	ls_epc->bar[BAR_5].type = BAR_RESERVED;
>> +	ls_epc->bar[BAR_5].type = BAR_64BIT_UPPER;
>>   	ls_epc->linkup_notifier = true;
>>
>>   	pcie->pci = pci;
>> diff --git a/drivers/pci/controller/dwc/pcie-keembay.c b/drivers/pci/controller/dwc/pcie-keembay.c
>> index 2666a9c3d67e..5a00b8cf5b53 100644
>> --- a/drivers/pci/controller/dwc/pcie-keembay.c
>> +++ b/drivers/pci/controller/dwc/pcie-keembay.c
>> @@ -313,11 +313,11 @@ static const struct pci_epc_features keembay_pcie_epc_features = {
>>   	.msi_capable		= true,
>>   	.msix_capable		= true,
>>   	.bar[BAR_0]		= { .only_64bit = true, },
>> -	.bar[BAR_1]		= { .type = BAR_RESERVED, },
>> +	.bar[BAR_1]		= { .type = BAR_64BIT_UPPER, },
>>   	.bar[BAR_2]		= { .only_64bit = true, },
>> -	.bar[BAR_3]		= { .type = BAR_RESERVED, },
>> +	.bar[BAR_3]		= { .type = BAR_64BIT_UPPER, },
>>   	.bar[BAR_4]		= { .only_64bit = true, },
>> -	.bar[BAR_5]		= { .type = BAR_RESERVED, },
>> +	.bar[BAR_5]		= { .type = BAR_64BIT_UPPER, },
>>   	.align			= SZ_16K,
>>   };
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
>> index 18460f01b2c6..e55675b3840a 100644
>> --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
>> +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
>> @@ -850,9 +850,9 @@ static const struct pci_epc_features qcom_pcie_epc_features = {
>>   	.msi_capable = true,
>>   	.align = SZ_4K,
>>   	.bar[BAR_0] = { .only_64bit = true, },
>> -	.bar[BAR_1] = { .type = BAR_RESERVED, },
>> +	.bar[BAR_1] = { .type = BAR_64BIT_UPPER, },
>>   	.bar[BAR_2] = { .only_64bit = true, },
>> -	.bar[BAR_3] = { .type = BAR_RESERVED, },
>> +	.bar[BAR_3] = { .type = BAR_64BIT_UPPER, },
>>   };
>>
>>   static const struct pci_epc_features *
>> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
>> index 06571d806ab3..31aa9a494dbc 100644
>> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
>> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
>> @@ -1993,7 +1993,7 @@ static const struct pci_epc_features tegra_pcie_epc_features = {
>>   	.msi_capable = true,
>>   	.bar[BAR_0] = { .type = BAR_FIXED, .fixed_size = SZ_1M,
>>   			.only_64bit = true, },
>> -	.bar[BAR_1] = { .type = BAR_RESERVED, },
>> +	.bar[BAR_1] = { .type = BAR_64BIT_UPPER, },
>>   	.bar[BAR_2] = { .type = BAR_RESERVED, },
>>   	.bar[BAR_3] = { .type = BAR_RESERVED, },
>>   	.bar[BAR_4] = { .type = BAR_RESERVED, },
>> diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
>> index d52753060970..f873a1659592 100644
>> --- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
>> +++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
>> @@ -426,9 +426,9 @@ static const struct uniphier_pcie_ep_soc_data uniphier_pro5_data = {
>>   		.msix_capable = false,
>>   		.align = 1 << 16,
>>   		.bar[BAR_0] = { .only_64bit = true, },
>> -		.bar[BAR_1] = { .type = BAR_RESERVED, },
>> +		.bar[BAR_1] = { .type = BAR_64BIT_UPPER, },
>>   		.bar[BAR_2] = { .only_64bit = true, },
>> -		.bar[BAR_3] = { .type = BAR_RESERVED, },
>> +		.bar[BAR_3] = { .type = BAR_64BIT_UPPER, },
>>   		.bar[BAR_4] = { .type = BAR_RESERVED, },
>>   		.bar[BAR_5] = { .type = BAR_RESERVED, },
>>   	},
>> @@ -445,11 +445,11 @@ static const struct uniphier_pcie_ep_soc_data uniphier_nx1_data = {
>>   		.msix_capable = false,
>>   		.align = 1 << 12,
>>   		.bar[BAR_0] = { .only_64bit = true, },
>> -		.bar[BAR_1] = { .type = BAR_RESERVED, },
>> +		.bar[BAR_1] = { .type = BAR_64BIT_UPPER, },
>>   		.bar[BAR_2] = { .only_64bit = true, },
>> -		.bar[BAR_3] = { .type = BAR_RESERVED, },
>> +		.bar[BAR_3] = { .type = BAR_64BIT_UPPER, },
>>   		.bar[BAR_4] = { .only_64bit = true, },
>> -		.bar[BAR_5] = { .type = BAR_RESERVED, },
>> +		.bar[BAR_5] = { .type = BAR_64BIT_UPPER, },
>>   	},
>>   };
>>
>> diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c
>> index 657875ef4657..9b3f5391fabe 100644
>> --- a/drivers/pci/controller/pcie-rcar-ep.c
>> +++ b/drivers/pci/controller/pcie-rcar-ep.c
>> @@ -440,13 +440,13 @@ static const struct pci_epc_features rcar_pcie_epc_features = {
>>   	/* use 64-bit BARs so mark BAR[1,3,5] as reserved */
>>   	.bar[BAR_0] = { .type = BAR_FIXED, .fixed_size = 128,
>>   			.only_64bit = true, },
>> -	.bar[BAR_1] = { .type = BAR_RESERVED, },
>> +	.bar[BAR_1] = { .type = BAR_64BIT_UPPER, },
>>   	.bar[BAR_2] = { .type = BAR_FIXED, .fixed_size = 256,
>>   			.only_64bit = true, },
>> -	.bar[BAR_3] = { .type = BAR_RESERVED, },
>> +	.bar[BAR_3] = { .type = BAR_64BIT_UPPER, },
>>   	.bar[BAR_4] = { .type = BAR_FIXED, .fixed_size = 256,
>>   			.only_64bit = true, },
>> -	.bar[BAR_5] = { .type = BAR_RESERVED, },
>> +	.bar[BAR_5] = { .type = BAR_64BIT_UPPER, },
>>   };
>>
>>   static const struct pci_epc_features*
>> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
>> index 068155819c57..8de321e1c342 100644
>> --- a/drivers/pci/endpoint/pci-epc-core.c
>> +++ b/drivers/pci/endpoint/pci-epc-core.c
>> @@ -104,7 +104,8 @@ enum pci_barno pci_epc_get_next_free_bar(const struct pci_epc_features
>>
>>   	for (i = bar; i < PCI_STD_NUM_BARS; i++) {
>>   		/* If the BAR is not reserved, return it. */
>> -		if (epc_features->bar[i].type != BAR_RESERVED)
>> +		if (epc_features->bar[i].type != BAR_RESERVED &&
>> +		    epc_features->bar[i].type != BAR_64BIT_UPPER)
>>   			return i;
>>   	}
>>
>> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
>> index c021c7af175f..c22f8a6cf9a3 100644
>> --- a/include/linux/pci-epc.h
>> +++ b/include/linux/pci-epc.h
>> @@ -192,12 +192,15 @@ struct pci_epc {
>>    *		   NOTE: An EPC driver can currently only set a single supported
>>    *		   size.
>>    * @BAR_RESERVED: The BAR should not be touched by an EPF driver.
>> + * @BAR_64BIT_UPPER: Should only be set on a BAR if the preceding BAR is marked
>> + *		     as only_64bit.
>>    */
I think another patch is required to handle the set_bar().
Set BARx+1 type as BAR_64BIT_UPPER in set_bar() callback if
the epf_bar->flags has PCI_BASE_ADDRESS_MEM_TYPE_64.
>>   enum pci_epc_bar_type {
>>   	BAR_PROGRAMMABLE = 0,
>>   	BAR_FIXED,
>>   	BAR_RESIZABLE,
>>   	BAR_RESERVED,
>> +	BAR_64BIT_UPPER,
>>   };
>>
>>   /**
>> @@ -207,7 +210,7 @@ enum pci_epc_bar_type {
>>    * @only_64bit: if true, an EPF driver is not allowed to choose if this BAR
>>    *		should be configured as 32-bit or 64-bit, the EPF driver must
>>    *		configure this BAR as 64-bit. Additionally, the BAR succeeding
>> - *		this BAR must be set to type BAR_RESERVED.
>> + *		this BAR must be set to type BAR_64BIT_UPPER.
>>    *
>>    *		only_64bit should not be set on a BAR of type BAR_RESERVED.
>>    *		(If BARx is a 64-bit BAR that an EPF driver is not allowed to
>> --
>> 2.53.0

I think below comment should be removed.

  *              only_64bit should not be set on a BAR of type BAR_RESERVED.
  *              (If BARx is a 64-bit BAR that an EPF driver is not 
allowed to
  *              reprogram, then both BARx and BARx+1 must be set to type
  *              BAR_RESERVED.)
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